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Question
Find the inverse of the matrices (if it exists).
`[(-1,5),(-3,2)]`
Solution
A = `[(-1,5),(-3,2)]`
|A| = `[(-1,5),(-3,2)] = - 2 + 15 = 13 ne 0`
Therefore, A-1 exists.
A11 = 2, A12 = 3, A21 = -5, A22 = - 1
adj A = `[(2,3),(-5,-1)] = [(2,-5),(3,-1)]`
`A^-1 = 1/abs A (adj A)`
`= 1/13 [(2,-5),(3,-1)]`
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